I've been a proud Spotify user for a long time now, and I was really looking forward to this update. Tonight the Spotify team has started rolling out the 0.4.3 version of its official client (which was already great on the Mac) which features a lot of new features, improvements and touches. This update is so important the team itself is calling it a "Monster Release".
First, Spotify is getting social: you can now link your Spotify account to your Facebook profile, share playlists and tracks with your friends, see which songs are the most shared and liked. I don't know how much I'll use this, but no doubt it was the right thing to do. Also, the interface for this looks very well realized and simple to use.
The big news is that Spotify can now import your local iTunes Library, thus making this service the first and most important competitor to Apple's music player and alleged future streaming platform. Well, it's not that Spotify can import actual .mp3 files into its database, it simply gets a link with the track's information and merges it with its servers so that you'll be able to have your songs available for streaming - but those aren't your mp3 files on the cloud. It's a clever implementation. Also, Spotify now uses Gracenote to keep the info about songs and artists more accurate as possible, which is a very welcomed addition.
Last, there are some minor UI tweaks and new buttons to streamline the experience and make it easier to star tracks and navigate through tracks.
Well done, Spotify.